Bailey ac Bailey: Woody Plants of National Parks 229 



Involucre composed of more than 6 bracts. 



Flowers with pappus of papery scales; corollas yellow; leaves 



sticky-glutinous GUTIERREZIA, p. 236. 



Flowers with pappus of hair-like bristles. 



Stems mostly 4-angled; plants nearly leafless 



Daccharis sergiloides, p. 255. 



Stems not 4-angled; plants leafy at least before flowering 

 (nearly leafless in Debhia). 



Flowers yellow. 



Heads cyhndnc to top-shaped; bracts of involucre 

 herbaceous, sometimes thinnish but not 

 papery nor fringed. 



Bracts of involucre in more or less distinct 

 vertical rows; ray flowers none. 



Plants nearly leafless; heads with scales 

 on receptacle between the flowers 



BEBBIA, p. 237. 



Plants leafy at least before flov/ering; 

 heads without scales on the re- 

 ceptacle ..CHRYSOTHAMNUS, p. 237. 



Bracts of involucre not in distinct vertical 

 rows; flower heads usually with 1 to 

 several ray flowers (except in a few 

 species) ApLOPAPPUS, p. 243. 



Heads spherical; involucral bracts papery, the mar- 

 gins fringed ACAMPTOPAPPUS, p. 249. 



Flowers white or purplish-pink. 



Tall, erect shrubs; flowers purplish-pink, the heads 

 in small dense clusters at the ends of 

 densely leafy branches PLUCHEA, p. 249. 



Low, round-topped bushes ; flowers white, the heads 

 borne singly at the ends of sparsely leafy 

 branches ..Bricl^ellia oblongifoUa var., p. 251. 



Leaf-blades broader, oblong to egg-shaped or triangular, toothed or not toothed, or 

 if narrow, then the margins always toothed or lobed. 



Leaf-blades lance-shaped to broadly linear, the margins finely toothed, crowded 



near the ends of the smooth white stems BrickelUa longifolia, p. 251. 



Leaf-blades oblong or lance-shaped to egg-shaped or triangular. 



Leaf-blades toothed or lobed (except sometimes Trixis) ; pappus present or 

 none. 



Leaves whitish or grayish with a fine felt, toothed or irregularly lobed, 

 the margins often curled or crinkled; pappus scale-like or 

 none. 



Flowers greenish and inconspicuous; heads borne in the leaf-axils, 



in fruit becoming bur-like; pappus none 



FRANSERIA, p. 249. 



Flowers white; heads borne in flat-topped clusters at the ends of 



erect flowering stems; heads not changing in fruit; 



pappus of papery scales PARTHENIUM, p. 250. 



Leaves green, sometimes hairy but not woolly; pappus of hair-like 

 bristles. 



Leaf-blades broadly lance-shaped to egg-shaped or triangular. 



